<%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8"%>
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>Insert title here</title>
</head>
<body>
<%!
int i = 3; 
%>
操作成功!

<% 
response.setHeader("Refresh", "1");

%>
<h1>还有<%=i%>秒跳转回去</h1>
<% 
i--;
if(i <0)
{
	response.sendRedirect("exam_info.html");
	i=3;
}
%>
</body>
</html>